1. Field of the Invention
The present invention relates to a device for attaching a strip cover on a dewatering box in a paper machine.
2. Description of the Related Art
Covers or strip covers, which are utilized in the wet section of a paper or cardboard mill, are connected with the associated dewatering box as follows:
In one method the covers are guided in T-rails or dovetail guides. With this mounting method, there is clearance between the cover and the guide device, so that the cover can be pulled from the guide. This method of attachment has the advantage that the cover can be changed, without having to disassemble the entire dewatering element from the paper machine. A problem with this method is that clearance between the guide and the cover may cause oscillations or vibrations during operation.
In another method the covers are mounted rigidly on the dewatering box, using clamping or screw connections. Connections of this type are located across the entire paper machine width. Since this method doesn""t normally offer adequate accessibility, the entire dewatering element must be disassembled in order to change the cover.
What is needed in the art is a mounting device, which offers a rigid connection between the strip cover and the dewatering box and allows the cover to be changed without the need to dismantle the entire dewatering element.
The present invention provides a mounting device for attaching a strip cover on a dewatering box in a paper machine.
The invention comprises, in one form thereof, at least one connecting element, extending transversely to the machine direction, to attach the strip cover to the dewatering box preferably across the entire machine width. Fasteners secure the connecting element on the dewatering box in such a manner that it is adjustable, generally transversely to the machine direction, between a clamping position in which it presses the strip cover tightly against the dewatering box, and a release position in which the strip cover is released. At least one adjusting element is used for the adjustment of the connecting element, which is accessible from the operator or drive side of the paper machine.
This configuration offers not only a rigid, reliable connection between the strip cover and the dewatering box but, because the connection can be released on the operator and/or drive side, the hitherto dismantling of the entire dewatering element, in order to change a cover, is no longer required.
The connecting element, which is preferably in the embodiment of an angled section, can be located on a side of the dewatering box that extends transverse to the machine direction. The angled section engages the strip cover by a manner in which the strip cover is pressed against the dewatering box. The connecting element is positioned in such a manner that during each respective adjustment, relative to the dewatering box, it is moved in a machine cross-direction, as well as a vertical direction to the surface of the strip cover, facing toward the angled section. Due to the movement component, extending vertically to the strip surface, the strip cover is pressed decisively against the dewatering box by the angled section.
The fasteners, which are preferably in the embodiment of bolts, are anchored in the dewatering box and may extend through the guiding slots, that are located in the connecting element, whereby they are always equipped with a head on the free end.
In a preferred, practical embodiment of the device, in accordance with the present invention, the guiding slots slant, relative to the machine cross-direction. Such slanting guiding slots ensure that an adjustment of the connecting element, in a cross-direction, also always creates a movement component vertical to the surface of the strip cover, which presses the strip cover against the dewatering box.
In addition, the connecting element can be positioned so that, simultaneously with a movement into its clamping position, it is pressed against the relating side of the dewatering box, which extends transverse to the machine direction. This removes any remaining looseness in the machine direction.
In its clamping position, the connecting element rests, free from play, laterally against the dewatering box. The head of a respective fastener can act together with a corresponding angled surface of the connecting element, in order to affect the simultaneous pressing of the connecting element against the appropriate side of the dewatering box that extends transverse to the machine direction.
In a preferred, practical embodiment of the device, in accordance with the current invention, at least one connecting element is located on each of the two sides of the dewatering box, extending transversely to the machine direction.
Basically, a single connecting element, extending essentially across the entire machine width, or several connecting elements extending across sections of the machine width, may be located on any respective side. In accordance with a functional, practical design, two connecting elements are provided on at least one side of the dewatering box that extends transverse to the machine direction. The connecting elements each extend across a section of the machine width and are adjustable from opposite sides of the paper machine. The connecting elements positioned on a respective side of the dewatering box can be of the same length and extend at least across half the machine width.
In certain instances it is useful if the fasteners are detachable. The adjusting element includes an adjusting screw. In principle, the adjusting screw can also be detachable. A washer can be provided between the head of the fastener and the connecting element. This may, for example, consist of a different material than the fastener. Brass or bronze washers, or washers of a material similar to the fastener may be utilized.
A sleeve that rolls on the edge of the appropriate guide slot can be slipped onto the fasteners, which are preferably in the embodiment of bolts. A sliding friction between the connecting element and the fastener is thereby avoided.
An adjusting element is allocated to a respective connecting element and may be located either on one side of the paper machine or, specifically in the instance of a connecting element that extends at least essentially across the entire machine width, on the operator side, as well as on the drive side of the paper machine. If, for example, two connecting elements are provided on a respective side of the dewatering box, it may be practical to adjust one from the operator side and the other from the drive side, by way of corresponding adjusting elements.
In a functional practical embodiment, the adjusting element includes an adjusting screw, located at the dewatering box, which is connected with the connecting element, such that the connecting element is adjustable in both directions by way of the adjusting screw.
The connecting element can be configured such that movement into its clamping position can be accomplished by adjustment toward the outside or adjustment toward the inside. The connection is released in the respective opposite direction. The connecting element can be positively interlocked, for example, through an assembly angle, with the adjusting element that is located in the dewatering box. The adjusting element specifically includes an adjusting screw or a locating screw.